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BackgroundThe use of non-contrast cardiac computed tomography measurements to predict heart failure (HF) has not been studied. In the present study we evaluated the prognostic value of left ventricular area adjusted for the body surface area (LVA-BSA) measured by non-contrast cardiac CT to predict incident HF and cardiovascular disease (CVD) events.MethodsWe studied left ventricular dimensions and calculated LVA-BSA in 6781 participants of the MESA study (mean age: was 62 ± 10 years, 53% females; 62% non-white) free from prior HF who underwent non-contrast cardiac CT to evaluate the coronary artery calcium score (CAC) at baseline and were followed up for a median of 10.2 years.ResultsDuring follow up, 237 (3.5%) incident HF and 475 (7.0%) CVD events occurred. After adjustment for clinical variables and CAC, LVA-BSA was significantly associated with incident HF (hazard ratio [HR]: 1.10 per 100 mm2/m2, p

Rationale and objectivesVascular calcification independently predicts cardiovascular disease (CVD), and computed tomography (CT) is a useful tool to evaluate and quantify not only coronary but also thoracic aortic calcification (TAC). Previous TAC progression reports were limited to dialysis and renal transplant patients. This is the first study to evaluate TAC progression in a large multiethnic cohort without clinically evident CVD at entry.MethodsNon-contrast-enhanced cardiac CTs were obtained in 5886 of 6814 Multi-Ethnic Study of Atherosclerosis (MESA) participants (mean age, 62 years; 48% males; 40% white, 27% black, 21% Hispanic, and 12% Chinese). Baseline and follow-up TAC scores were derived.ResultsOverall, 4308 (73%) participants had no detectable baseline TAC. Mean follow-up duration was 2.4 ± 0.8 years, during which 12% developed TAC. The overall incidence rate was 4.8%/year and was greater with age across gender and ethnic groups; TAC incidence was significantly lower in blacks than whites. After adjustment for follow-up duration, regression analyses showed age, systolic blood pressure, antihypertensives, and smoking were associated with incident TAC. A total of 1578 (27%) participants had TAC at baseline with a positive association between average annual TAC change and baseline age. Although the overall median change was 32.9 (-1.4 to 112.2) Agatston units, 27% showed an annual score change of ≥100 and blacks showed the lowest median across ethnic groups; 22.7 (-3 to 86.8). Age, systolic blood pressure, lipid-lowering medication, diabetes, and smoking were associated with TAC progression.ConclusionsIn MESA, traditional CV risk factors were related to both TAC incidence and progression. Blacks had the lowest incidence and median change across ethnic groups, consistent with previous findings for coronary calcification.

Background The prevalence of overweight and obesity in Mexican schoolchildren has increased in the past three decades. Dietary pattern approaches to assess diet have been used to study the relation between nutrition and chronic conditions. Objective The objective of this study is to analyze the association between dietary patterns (DP) and overweight and obesity in Mexican schoolchildren. Methods We analyzed information from schoolchildren who participated in the National Health and Nutrition Survey 2012 (ENSANUT-2012). Dietary information was obtained through a 24-h recall of 2751 children (5-11 year). Foods were classified into 33 groups, and the DPs were identified by cluster analysis (k-means method). Weight and height were measured to estimate the body mass index (BMI), by classifying overweight if the Z score was >1 and [less than or equal to]2 standard deviations (SD), and obesity when the Z score was >2SD. To analyze the association, a Poisson regression model was used, adjusting by age, region, area of residence, socioeconomic status (SES), and the survey design. Results Four DPs were identified: 'Traditional', 'Industrialized', 'Varied', and 'Modern'. The 'Modern' DP was associated with obesity (PR = 1.7) (p < 0.05) compared with the 'Traditional' DP. Conclusions The 'Modern' DP could be influencing the development of obesity in Mexican schoolchildren. The promotion of healthy food and public health strategies to those food groups that should be discouraged are necessary to reverse the obesity epidemic in Mexican children., Author(s): Claudia Gabriela García-Chávez [sup.1], Juan A. Rivera [sup.2], Eric Monterrubio-Flores [sup.1], Sonia Rodríguez-Ramírez [sup.1] Author Affiliations: (1) Centro de Investigación en Nutrición y Salud, Instituto Nacional de Salud Pública., [...]

BackgroundThe American College of Cardiology (ACC)/American Heart Association (AHA) cholesterol management guidelines have significantly broadened the scope of candidates eligible for statin therapy.ObjectivesThis study evaluated the implications of the absence of coronary artery calcium (CAC) in reclassifying patients from a risk stratum in which statins are recommended to one in which they are not.MethodsMESA (Multi-Ethnic Study of Atherosclerosis) is a longitudinal study of 6,814 men and women 45 to 84 years of age without clinical atherosclerotic cardiovascular disease (ASCVD) risk at enrollment. We excluded 1,100 participants (16%) on lipid-lowering medication, 87 (1.3%) without low-density lipoprotein levels, 26 (0.4%) with missing risk factors for calculation of 10-year risk of ASCVD, 633 (9%) >75 years of age, and 209 (3%) with low-density lipoprotein

BackgroundThe transition from no coronary artery calcium (CAC) to detectable CAC is important, as even mild CAC is associated with increased cardiovascular events. We sought to characterize the anatomic distribution and burden of newly detectable CAC over 10-year follow-up.MethodsWe evaluated 3112 participants (mean age, 58 years; 64% female) with baseline CAC = 0 from the Multi-Ethnic Study of Atherosclerosis. Participants underwent repeat CAC testing at different time intervals (between 2-10 years after baseline) per the Multi-Ethnic Study of Atherosclerosis protocol. Among participants who developed CAC on a follow-up scan, we used logistic regression and marginal probability modeling to describe the coronary distribution and burden of new CAC by age, sex, and race after adjustment for cardiovascular risk factors and time to detection.ResultsA total of 1125 participants developed detectable CAC during follow-up with a mean time to detection of 6.1 ± 3 years. New CAC was most commonly isolated to 1 vessel (72% of participants), with the left anterior descending artery (44% of total) most commonly affected followed by the right coronary (12%), left circumflex (10%), and left main (6%). These patterns were similar across age, sex, and race. In multivariate models, residual predictors of multivessel CAC (28% of total) included male sex, African American or Hispanic race, hypertension, obesity, and diabetes. At the first detection of CAC >0, burden was usually low with median Agatston CAC score of 7.1 and 100.ConclusionNew-onset CAC most commonly involves just 1 vessel, occurs in the left anterior descending artery, and has low CAC burden. New CAC can be detected at an early stage when aggressive preventive strategies may provide benefit.

BackgroundLeft ventricular (LV) volume and mass have prognostic relevance. Overall size of the left ventricle as it appears in noncontrast CT is a composite of the ventricular volume and myocardial mass. We describe a method to estimate the LV size using a single cross-section in noncontrast CT and determined normal ranges on the basis of a large population cohort.MethodsThe Multi-Ethnic Study of Atherosclerosis with 6814 participants from 4 ethnicities who were free of known cardiovascular disease and enrolled between 2000 and 2002 form the basis of our analysis. LV size was calculated from a single cross-sectional slice obtained by either nonenhanced electron beam or multidetector CT. LV size was adjusted to body surface area to obtain the LV size index, which was adjusted for age, sex, race or ethnicity, hypertension, hyperlipidemia, and diabetes.ResultsThere were significant differences in LV size index by race which were further influenced by age and sex. Higher values were noted in men in all ethnic groups across all age groups. Similarly, LV size index uniformly decreased with age across all ethnic and sex categories. Caucasians had the lowest and African Americans had the highest LV size index across all age and sex categories. In multivariate regression analyses adjusted for age, sex, race or ethnicity, hypertension, hyperlipidemia, smoking, and diabetes mellitus, the significant differences were noted between male vs female (median difference, 17.5 cc/m(2); P < .001), ethnic groups (Caucasian, reference group; Asian, 3.7 cc/m(2); African American, 8.3 cc/m(2); and Hispanic, 5.6 cc/m(2); P < .001), and age groups (45-54 years, reference group; 55-64 years, -5.2 cc/m(2); 65-74 years, -11.4 cc/m(2); and 74-84 years, -12.5 cc/m(2)).ConclusionsThis study provides normative values for LV size as determined from a single, nonenhanced CT cross-section and indexed to body surface area, and it demonstrates that the LV size index varies by age, sex, and ethnic background.

Cellular responses elicited by cell surface receptors differ according to stimulus strength. We investigated how the high-affinity receptor for immunoglobulin E (IgE) modulates the response of mast cells to a high- or low-affinity stimulus. Both high- and low-affinity stimuli elicited similar receptor phosphorylation; however, differences were observed in receptor cluster size, mobility, distribution, and the cells' effector responses. Low-affinity stimulation increased receptor association with the Src family kinase Fgr and shifted signals from the adapter LAT1 to the related adapter LAT2. LAT1-dependent calcium signals required for mast cell degranulation were dampened, but the role of LAT2 in chemokine production was enhanced, altering immune cell recruitment at the site of inflammation. These findings uncover how receptor discrimination of stimulus strength can be interpreted as distinct in vivo outcomes.

ObjectiveWe evaluated family history as a predictor of incident and progressive coronary artery calcium (CAC) using data from the Multi-Ethnic Study of Atherosclerosis (MESA).BackgroundMESA is a multi-center prospective study of 6814 asymptomatic individuals. The relationship between family history of coronary heart disease (CHD) and CAC incidence or progression has not been described previously.MethodsA total of 5099 participants had detailed information about family history of CHD (late versus premature and parental versus sibling history). The mean time between CAC scans was 3.1 ± 1.3 years. The association of late versus premature family history was assessed against CAC change using multivariate regression model adjusted for demographics and cardiac risk factors.ResultsA family history of premature CHD was associated with an odds ratio (OR) of 1.55 (p < 0.01) for incident development of CAC after adjusting for risk factors and demographics. A premature family history was associated with 14.4 units (p < 0.01) greater volume scores compared to those with no family history in similarly adjusted models by median regression analysis. A combined parental and sibling family history was associated with the greatest incidence and progression in demographic-adjusted models. Caucasians demonstrated the most consistent predictive relationship between family history of premature CHD and incidence (p < 0.01) and progression (p < 0.05) of CAC, though no significant interaction with ethnicity was noted.ConclusionsFamily history of premature CHD is associated with enhanced development and progression of subclinical disease, independent of other risk factors, in a multiethnic, population-based study.

BackgroundWorldwide clinical practice guidelines for dyslipidemia emphasize allocating statin therapy to those at the highest absolute atherosclerotic cardiovascular disease (CVD) risk.Methods and resultsWe examined 5534 Multi-Ethnic Study of Atherosclerosis (MESA) participants who were not on baseline medications for dyslipidemia. Participants were classified by baseline coronary artery calcium (CAC) score (>0, ≥ 100) and the common clinical scheme of counting lipid abnormalities (LA), including low-density lipoprotein cholesterol ≥ 3.36 mmol/L (130 mg/dL), high-density lipoprotein cholesterol

Tree diseases contribute to significant economic and food losses in the agricultural sector. Early detection of phytosanitary problems in trees with non-destructive methods is essential to guarantee sustainable orange production. This study presents the findings of a designed methodology conducted to identify diseased orange trees in an orchard situated in the citrus belt of Mexico, specifically in the Rioverde region of San Luis Potosi. To accomplish this, we captured images using a multispectral camera with very high spatial resolution, which was mounted on an unmanned aerial vehicle. These images were used to construct a georeferenced orthomosaic of the orchard. Six thematic classes were established to distinguish various health levels among the trees. We employed several supervised classification algorithms at the pixel level, including Random Forest (RF), K-Nearest Neighbor (KNN), Spectral Angle Mapper (SAM), Support Vector Machine (SVM), and Maximum Likelihood (ML). Considering the classification accuracy achieved by each algorithm, they can be ranked as follows: Maximum Likelihood (ML) with 88.10%, Support Vector Machine (SVM) with 77.38%, Spectral Angle Mapper (SAM) with 76.19%, K-Nearest Neighbor (KNN) with 64.68%, and Random Forest (RF) with 61.90%. These results successfully identified the phytosanitary status of all the trees in the orchard with an acceptable level of accuracy, providing valuable management information for the grower. [ABSTRACT FROM AUTHOR]

This study aimed to delineate the most suitable areas for sustainable citrus production by integrating multi-criteria decision analysis, time-series remote sensing, and principal component analysis in a portion of the northern citrus belt of Mexico, particularly in the Rioverde Valley. Fourteen specific factors were grouped into four main factors, i.e., topography, soil, climate, and proximity to water sources, to carry out a multi-criteria decision analysis for classifying production areas according to suitability levels. To explore the effect of precipitation on land suitability for citrus production, we analyzed the historical record of annual precipitation estimated by processing 20-year NDVI daily data. The multi-criteria model was run for every precipitation year. The final map of land suitability was obtained by using the first component after principal component analysis on annual land suitability maps. The results indicate that approximately 30% of the study area is suitable for growing orange groves, with specific areas designated as suitable based on both mean annual precipitation (MAP) and principal component analysis (PCA) criteria, resulting in 84,415.7 ha and 95,485.5 ha of suitable land, respectively. The study highlighted the importance of remotely sensed data-based time-series precipitation in predicting potential land suitability for growing orange groves in semiarid lands. Our results may support decision-making processes for the effective land management of orange groves in the Mexico's Rioverde region. [ABSTRACT FROM AUTHOR]